The present invention relates generally to air bag systems and more specifically to side impact occupant protection systems.
It has been proposed to protect vehicle occupants during a side impact collision to introduce an air bag between the occupant's torso and the interior of the vehicle. U.S. Pat. No. 3,617,073 is illustrative of a system in which the air bag protective system is located within a vehicle door. British Patent Specification 1 450 666 introduces the air bag from a top rail or roof while British Patent 2 232 936B shows an air bag formed within a seat.
With regard to seat mounted air bag systems it is desirable for the air bag and its associated mounting hardware to be constructed in a way that it is compatible with seat design and does not interfere with occupant comfort. All known air bag technologies mount the air bag in a rigid housing with a rigid cover about the air bag. This type of construction if placed behind the soft, compliant foam padding of the seat will reduce the resiliency of the padding lessening occupant comfort.
It is an object of the present invention to provide a side impact system that is compact in design and light-weight. A further object of the invention is to provide a side impact air bag module that is substantially smaller than the height of the back of the seat, thereby permitting the air bag module to be mounted at one of many desirable locations within the seat back without distracting from occupant comfort.
Accordingly, the invention comprises: a side impact occupant protection system including: an air bag module, having a soft exterior adapted to be placed adjacent a resilient interior portion of a seat back of an automotive seat. The system includes a channel having a key-hole shaped cross-section including a first cylindrical wall portion having a wide first diameter and a second portion having two spaced parallel sides forming an open top through which inflation gas may flow into an adjacent air bag. The distance across the space between the sides is less than that of the first diameter. The channel additionally includes a first end and a second end, the first end is substantially closed by a first end plate and includes a small opening therein. A cylindrically shape air bag inflator is fitted to and secured within the cylindrical portion of the channel. The inflator has at least one gas exit port directing inflation gas into the open top and thereafter into the air bag. The air bag is disposed, prior to activation of the inflator, in a compacted configuration over the top and about the sides of the channel such that opposing end sections of the air bag lie adjacent to a corresponding side. The system includes clamping means running along substantially the entire length of each channel side for clamping the end section of the air bag to the channel; wherein the clamping means, adjacent the air bag end sections, does not extend outwardly beyond the exterior of the cylindrical portion. The air bag is retained about the channel bag by a soft flexible outer shell.